ATel 17990: GTC spectroscopy of MAXI J1750-327

We report on optical spectroscopy of the recently discovered X-ray transient MAXI J1750-327 / EP J175003.0-324244 (ATels #17963, #17964), whose multi-wavelength properties are consistent with a black hole X-ray binary in outburst (ATels #17969, #17971, #17974, #17977, #17978, #17979, #17983, #17988). ...